关键词: 杨树, 镉胁迫；氮；生长；光合特性

Abstract:

In order to investigate the mechanism of plant detoxification against heavy metal, the effects of cadmium stress by adding nitrogen on growth and photosynthetic characteristic of poplar plants were identified, the results showed that addition of Cd(NO3)2 or CdCl2 by adding NH4HCO3 to the poplar culture soil stimulated the growth of poplar plants, increased the content of chlorophyll a (Chl a) and chlorophyll b (Chl b), as well as photosynthesis. However, the addition of CdCl2 to the soil inhibited the growth of poplar plants and led to a decrease in photosynthetic pigment content and photosynthesis. The results of our study suggested that the addition of cadmium to the soil together with nitrogen partially reversed the toxic effect of cadmium on poplar plants, and nitrogen may play an important physiological role in detoxifying plants from heavy metals.

Key words: poplar, cadmium stress； nitrogen； growth； photosynthetic characteristic